I see you mentioned you never clip your chickens wings. As a general principle, that's fine. But for this particular girl, you might want to reconsider and do a full bilateral clip.
I too was remiss to clip wings to keep my flock in their electrified pen. Over the course of three days I started out clipping a single wing, primaries only on the worst offenders. They all got out the next day. I continued going with more aggressive clips including both wings and both primaries and secondaries in various combinations based on how easily a specific bird was escaping. On the third day, before getting really aggressive with the clipping, one of my EEs escaped and was killed by the neighbors German Shepherd.
It only takes one meeting for the bird and any predator outside the enclosure for disaster to strike.
